1. Field of the Invention
The present invention relates to an omnidirectional azimuth and tilt angle meter which can detect a tilt angle and a tilt azimuth angle of a structure or a moving body.
2. Description of the Relevant Art
Though there is a demand for continuously detecting an omnidirectional tilt angle in an industrial robot, a ship, a special vehicle, civil engineering and construction works or the like, in this case often the detected value cannot be utilized for automatic control and the like unless a maximum tilt angle and azimuth angle thereof are detected on a real-time basis.
As a tilt angle measuring apparatus, an apparatus displaying a tilt angle about only one axis has been heretofore known. However, if it is intended to seek for a maximum tilt angle and an azimuth angle thereof over the entire direction, the apparatus is placed horizontally at a measuring point and rotated over 360 degrees about the measuring point by manual operations, then it is set in the direction indicating a maximum angle of elevation or depression, thereafter a tilt angle indicated at that time is read out, and both the set azimuth angle and the read tilt angle are jointly utilized as measured data.
While such works relying upon manual operations can be adapted for a wide range of azimuth angles, it necessitates much measuring time, and it is difficult to obtain precise omnidirectional tilt data at a given time point.
Moreover, it is impossible to use the data for automatic control which is especially demanded in recent years and which necessitates to process on a real-time basis, and so the use of such apparatus is extremely limited.
Therefore, one example of relevant art in which two tilt angle measuring apparatus each measuring a tilt angle about only one axis are prepared and disposed at right angles to each other, and a maximum tilt angle and an azimuth angle are calculated from the measured data of the both measuring apparatus (Laid-Open Japanese Patent Specification No. 62-280608 (1987)), has been already proposed by the same inventor as the inventor of the present invention.
In this example of relevant art, two tilt angle sensors for detecting a tilt angle about one axis directed in a given direction are swingably disposed on a structure to be measured with their axes directed at right angles to each other, and the tilt angle sensors have their measuring movable planes always directed vertically.
And a maximum tilt angle and a tilt azimuth angle are calculated from the tilt angles detected by the respective tilt angle sensors.
However, due to the fact that the tilt angle sensor is disposed so as to be freely swingable with respect to a structure, in the case where it swings, it necessitates some time period until the sensor becomes stabilized, and so, for a structure whose attitude changes in a short period of time, a response speed of the sensor becomes an issue.
Also, in view of the amplitude of swinging of the tilt angle sensor, it is necessary to secure a large swinging space, and this becomes a bar against reduction in size.
Furthermore, in order to obtain a maximum tilt angle and its azimuth angle on the basis of detection signals issued from the two tilt angle sensors, complicated calculation is necessitated, hence digital calculation by means of a computer becomes essentially necessary, and it resulted in a high cost.